First of all, keep in mind that I am unable to diagnose you because I am unable to examine you, this forum is for educational purposes.  From the symptoms you describe, I suspect your daughter is having migraine (or migraine variant) headaches.  Migraine headaches are severe throbbing headaches, that can be associated with photophobia (bright lights make headache worse), phonophobia (sounds make headache worse), nausea/vomiting, motion sensitivity (movement make headache worse).  These headaches typically start in the teenage years (but can start even earlier), and often (but not always) run in families.  After the headache begins they are very difficult to stop.  Medications given for migraine need to be given quickly and patients with an aura (warning such as flasing lights, squiggly lines, etc.) have the advantage to treat their headache before the pain starts.  Once the pain has started full force, sometimes only sleep or IV medications can stop the pain.  On occasion migraine headaches can transform and change into a daily headache with intermittent exacerbation of severe headaches.  This type of "transformed migraine headache" or as it is sometimes reffered to as "status migrainosus" often require IV transfusions to break the cycle of the headaches.
   Their are 3 muscles around the scalp that have been implicated in headaches, the frontalis, temporalis and occipitalis. These muscles do not have pain fibers, but the facia/aponeurosis (connective tissue) associated with them does.  Some headache syndromes such as nummular headaches and "ponytail headache" are thought to be due to irritation of the muscle system.  These muscles are also implicated in precipitating migraine headaches and Botox injections into these muscles have been demonstrated to be very effective in treating these headaches.  The cause of the headache (besides the likely genetic component) is unknown.
  Given the symptoms you describe I would recommend that you see your neurologist (or a neurologist that specializes in headaches) for a 3-5 day (usually outpatient) IV infusion treatment to break the cycle of her headaches.  Medications used during these treatments often include DHE, depakote, magnesium, phenergan/kytril, valium, and toradol.  Sometimes a short taper of steroids is also used.  I would then recommend that you see your neurologist/headache specialist for possible Botox injection in the Frontalis, temporalis, occipitalis muscles for headache prevention.  I would also recommend that you have an MRI of your brain with contrast to rule out any secondary cause of your headache.  A psychological cause for severe headaches with nausea and vomiting would be Very rare in a 15 year old.  I would take her pain seriously and insist on aggressive treatment.
I hope this has been helpful.

A related discussion, Is this serious? was started.

I was wondering about Headaches, my son seems to get them alot. He's had 4 major head traumas- closed head injuries. MRI came back clear except for sinus. X-rays show brain stem compression some Brain Damage- which is true he has short term memory loss, CD>ODD> ADHD nos, EBD, reading and Math Learning disability. The doctor thinks siezures- and did a half hour EEG ( was supoose to be 2 hrs )which was normal- and I questioned them because they just want to put him on medication. Now they want to do a 48hour video- with EEG with the stuff that initiates headaches math and reading- and confusing problems or stress questions. His father was the last to see him at a 6th grade level- before he caused the abuse- now my sons at a 2nd grade reading level and 4th grade Math level. He has dreams about lots of numbers and it confuses him. He also suffers from dehydration and low minerals. Vitamins have helped like Spirulina, Iron, Multivitamins, and 5-HTP. Spirulina- is good for cleaning out toxins and rebuilding the trace minerals our bodies need. They say ADHD children have lower counts of Iron. Multi Vitamins to insure some extra nutrition, and 5-HTP has triptophan which has the natural seretonin to help with the brain. My son has improved with encouragement and praise. Now that hes back in school he's getting As and Bs- although he has behavior problems. I think I would feel better knowing exactly whats up with the headaches- he's still having after 2 years. Please share your story- and any advice.

I have migraines myself. I had one that lasted six weeks until I got to a neurologist who knew something about migraines. He put me on a three day treatment of a medicine called Frova. When i took it as directed for those three days, it broke the cycle of the migraine. He then changed up some of the medications I take (I have fibromyalgia) and that really seemed to help.

As the doctor told you, you need to see a neurologist who specializes in treating migraines. I am not telling you that your daughter will never suffer another headache/migraine, but she could have the the correct medication that would stop them quickly if she gets to the correct doctor. Good luck and God bless!

My daughter has had a spinal tap, an MRI and a CT Scan and I am told all those tests are coming back normal.  

The headaches seem to be getting worse.   In addition to the medicines she is on, it is now getting to one to two times a week we have to go to the doctors office or ER to get a shot to get the headache to a bearable state.  

When these headaches are at its peak it hurts to even move her hair around.  The top of the head is just so tender.

I would thank any feedback.

Many Regards,